E77 – 98 Standard Test Method for Inspection and Verification of Thermometers, Calibration-temperature instrumentation, Liquid-in-glass thermometers. Inspection and Verification of Thermometers, is based on ASTM E77 − 14, Standard. Test Method . E1 Specification for ASTM Liquid-in-Glass Thermometers. Buy ASTM E() Standard Test Method for Inspection and Verification of Thermometers from SAI Global.
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Scale corrections should always be applied in the use of these standards.
Need more than one copy? However, these procedures may be applied to other liquid-in-glass thermometers.
ASTM E77 – 07 Standard Test Method for Inspection and Verification of Thermometers
If the pigment in the scale etchings washes out or fades, the thermometer will be difficult to read. This standard is not included in any packages. The liquid should emerge into the bore with no separation. By softly tapping on a soft spongy material or against the hand it usually is possible to bring the liquid together in the bulb. A number in parentheses indicates the year of last reapproval.
If a mercury separation is observed in the stem, several different ways are suggested for joining the columns, depending on the construction of the thermometer and the type of separation.
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ASTM E77 – 14e1 – Standard Test Method for Inspection and Verification of Thermometers
A slight tapping of the 4 E 77 — 98 thermometer against the palm of the hand will facilitate this joining. Heat the thermometer to the selected reference point on the main scale, aatm the temperature for at least 15 min, and determine the scale correction at this point. Heat the thermometer again to the selected reference e777 on the main scale, keep it at this temperature for h. Its electrical resistance is determined by comparison with a standard resistor, using a potentiometer, a Kelvin-type double bridge, or a Wheatstone bridge, preferably of the Mueller type or an AC resistance bridge.
ASTM E77 – 14e1
It is frequently a good practice to immerse only the bulb of the thermometer. Allow to cool wstm. Thermometers that have a contraction chamber below the lowest graduation are likely to develop separations either in the chamber or above it. Gentle tapping of the thermometer while held upright will cause the bubbles to rise to the surface.
If the document is w77 or amended, you will be notified by email. As the voice of the U. This keeps the viscosity of the asttm in the capillary low and aids in hastening drainage. Normally, the effect of taper in the capillary or nonlinearity in the expansion characteristics of organic liquids is manifested by a gradual change in the spacing of the graduations. For fractionally graduated thermometers a calibrated set of the following thermometers is recommended.
More complete information on the construction and use of primary standard thermometers may be obtained from NIST SP In the case of ASTM thermometers, the diameter limits r77 over the entire length of the section of the thermometer being tested. Under these conditions oxidation of the mercury will occur and will normally be evidenced by the production of crystals of red oxide of mercury after 10 to 12 h of exposure.
Tapping the tube against the asfm or the bulb on a soft spongy material, such as a rubber stopper, usually will bring the liquid together. The choice of a secondary standard will be governed by various factors. Current edition approved Nov. It is the responsibility of the user of this standard to establish appropriate ast, and health practices and determine the applicability of regulatory limitations prior to use. The bulb should be allowed to warm up slowly. As the ice melts it will be necessary to drain off some of the water and add more crushed ice.
Discard any cloudy or unsound portions.
The most common types of foreign matter which should be cause for rejection are glass chips, particles of dirt or lint, oxide of mercury either red, yellow, or blackproducts of glass weathering commonly called white deposit, and stones or iron spots traceable to faulty glass fabrication.
In all cases only the current version of the standard as published by ASTM is to astj considered the official document. In order that it shall be satisfactory for such use, the thermometer should meet the requirement that the ratio of resistances at the steam and ice points shall be greater than 1. It is only necessary to have a liquid-in-glass thermometer completely calibrated one time.